Maps, atlases and globes, Operation Research

Maps, Atlases and Globes:

Maps illustrate the distribution of many things that occur on the surface of the earth. Information is presented by the use of a vast array of symbols, codes, and colours that attempt to communicate such features as shape, size, outline, pattern, arrangements, land relief or elevation, and the distribution of statistical values of an actual or relative quantity. Thus, the map user has the graphic means which make it easy and efficient to recognise, compare and examine patterns, relationships, surface features, locational data, scientific data, places, ocean cur-rents, geological formations, climate, weather, demographic distributions, political bound aries, economic data, agricultural capabilities, industrial production, military development, etc. The communication should be made easier by adoption of familiar symbols and structures. The legend assignment, colour charting, relief protection planning should be symbolic to one another. There are a variety of ways in which maps are presented and stored. The following are some:

Atlas: The atlas is a volume consisting of a collection of maps. Atlases are available in various dimensions. They are intended for individual use.

Wall Maps: Wall maps are considered to be entities, meaning they are unbound. They are usually 40-65 inches wide. It is important to know the map scale. Wall maps are intended for display and group use. They can be folded, mounted on spring rollers, or attached to dowels for hand rolling.

Bound Wall Maps: Bound wall maps are designed to be attached to a tripod or stand permitting them to be flipped over.

Overhead Transparencies: Maps on overhead transparencies are designed to be used exclusively on an overhead projector. Information can be added by the use of overlays or can be written on to transparencies with water-soluble ink. '

Relief Maps: Relief maps provide a three-dimensional perspective of the earth's surface. The relief, to be effective, must be grossly exaggerated in some of its proportions. For example, if a relief map of the world 72 inches square were to depict Mount Everest concretely (5 + miles high) in relief, it would be less than 1/60 of an inch high.

A map is a representation of a part or the whole of the surface of the earth or of a celestial body, delineated on a plane surface, each point in the drawing intended to correspond to a geographical or celestial position. It may be of a country, state, city, village or of a still smaller area irrespective of the scale or extent of area. Maps are of various types, such as physical maps, political maps, thematic maps (historical, statistical, ethnological, etc), Indian maps are issued by the Survey of India, Debra Dun.

An atlas is a volume consisting of a collection of maps. It may also contain photographs and other supplementary material. The Britannica Atlas, Hammond Medalline Word Atlas and Times Atlas of the World are three important examples of atlases. A globe is a spherical representation of the earth. Maps, atlases, and globes form an important source of geographical information. These are; therefore, a useful part of any library collection.